cosmopolitan/libc/stdio/fclose.c

60 lines
2.7 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=8 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/assert.h"
#include "libc/calls/calls.h"
#include "libc/errno.h"
#include "libc/mem/mem.h"
#include "libc/runtime/runtime.h"
#include "libc/stdio/internal.h"
#include "libc/stdio/stdio.h"
/**
* Closes standard i/o stream and its underlying thing.
*
* @param f is the file object, which is always free if it's heap,
* otherwise its resources are released and fields updated
* @return 0 on success or -1 on error, which can be a trick for
* differentiating between EOF and real errors during previous
* i/o calls, without needing to call ferror()
* @see fclose_s()
*/
int fclose(FILE *f) {
int rc;
if (!f) return 0;
_fflushunregister(f);
fflush(f);
if (!f->nofree) {
free_s(&f->buf);
}
f->state = EOF;
if (f->noclose) {
f->fd = -1;
} else if (close_s(&f->fd) == -1) {
f->state = errno;
}
if (f->state == EOF) {
rc = 0;
} else {
errno = f->state;
rc = EOF;
}
free_s(&f);
return rc;
}